武汉理工材料概论重点.doc

Definition 材料的定义：The materials making up the surrounding world consist of discrete particles, having a submicroscopic size.材料制作了周围的世界由离散粒子,拥有一个亚微观的大小。Atomic structure and the nature of bonds(原子结构和化学键)metals and their alloys (metallic bonding 金属键)organic polymers 有机聚合物(covalent bonding and secondary bonding 共价键和二次键)ceramics (ionic bonding and covalent bonding离子键和共价键)Mechanical properties：力学性能Which reflect the behavior of materials, deformed by a set of forces （概念）这反映材料的行为, 使.残缺，使.变形Four basic types of stresses : tensile, compressive, shear ,torsion (拉力，压力，剪切力，扭转力)Physical properties:物理性能the behavior of materials subjected to the action of temperature, electric or magnetic fields, or light.材料的行为受到的动作温度、电场或磁场,或者光。电性能Electric properties磁性能Magnetic properties热性能Thermal properties光性能Optical propertiesChemical properties:化学性能Which characterize the behavior of material in a reactive environment. （概念）用材料的行为在一个无功的环境。The four basic aspects of materials science and technology are: manufacturing processing, structure, properties and performances这四个基本方面的材料科学和技术:生产加工、结构、性质和性能First, the processing of a material affects the structure, second the original structure and properties determine how we can process the material to produce a desired shape首先,在处理材料影响结构,第二个原始的结构和性质决定我们如何处理材料产生想要的形状一、METAL:（金属）1、金属最显著的特性：good conductors of heat and electricity (热导性，电导性)2、性能:are opaque to visible light; are hard, rigid; can undergo plastic deformation; have a high melting temperature.是不透明的,可见光;是很难的,严格的,可以进行塑性变形;有一个高熔点温度吗3、金属的晶体点阵： crystal structure（晶体结构） : body-centered cubic structure , face-centered cubic structure , hexagonal close-packed structure（体型、面型，六角形放射状） 4、 properties of alloys（合金的性能） :(more carbon ,more brittle.) have relatively high thermal and electrical conductivities; good energy absorption characteristics ;nonmagnetic properties(更多的碳,更脆弱)。有相对较高的热导率和电;良好的能量吸收特性;非磁性特性5、 铸铁概念：cast iron, essentially an alloy of iron, carbon and silicon, is composed of iron and from 2 to 6.67 percent carbon, plus manganese, sulfur, and phosphorus, and shaped by being cast in a mold. 铸铁,本质上是一种合金的铁、碳和硅,是由铁和从2到6.67%的碳,加上锰、硫、磷、和形状的被一个模子刻出来的。6、 The types and properties of cast iron ； white cast iron( hard , brittle ) , gray cast iron (brittle ,withstand large compressive loads but small tensile loads ), alloy cast iron , nodular or ductile cast iron (good castability ,toughness, good wear resistance ,low melting point ,and hardenability ), malleable cast iron (strength ,toughness, ductility ,and machinability)的类型和属性的铸铁;白口铸铁(硬而脆),灰口铸铁(脆,承受大压缩加载,但小拉伸加载),合金铸铁,结节或球墨铸铁(良好的铸造性能、韧性好,耐磨损、低熔点,和硬化性)、可锻铸铁(强度、韧性、延性、可加工性)7、carbon steels（碳钢）：low carbon steels（含碳0.050.32%）；medium carbon steels（含碳0.350.55%）；high carbon steels（含碳0.601.50%）8、不锈钢：there are three types of stainless steels:-the martensitic types；the ferritic types ；the austenitic types 有三种类型的不锈钢:马氏体类型;铁素体类型;奥氏体类型9、 advantages of using Al: one-third of the weight of steel ;good thermal and electrical conductivity ;high strength-to-weight ratio ;can be given a hard surface by anodizing and hard coating ;most alloys are weldable ;will not rust ;high reflectivity ;can be die cast ;easily machined ;good formability; nonmagnetic ;nontoxic and one third of the stiffness of steel.优势利用艾尔:三分之一的重量钢铁;良好的热和导电性;高强度重量比,可以得到一个坚硬的表面,阳极氧化和硬涂层;大多数合金焊;不会生锈;高反射率;可以压铸加工;良好的成型性能;很容易;无磁性,无毒,一个人的刚度的钢。10、 copper is known for its high thermal (热导性)and electrical conductivity.铜以其高热导和电导被知道11、crystal structure : body-centered cubic structure (barium), face-centered cubic structure (copper), 晶体结构:以身体为中心的立方结构(钡),面心立方结构(铜),hexagonal close-packed structure (zinc)六角拥挤不堪的结构(锌)二、CERAMIC（陶瓷）1、The property of ceramics （陶瓷的性质） Extreme hardness（硬度高） Heat resistance 耐热性 Corrosion resistance耐蚀性 Low electrical and thermal conductivity 低电和热导率 Low ductility (brittleness)低韧性(脆性)2、Porosity（孔隙度）Open porosity: refers to the network of pores in a material that is open to the surface and into which a liquid such as water can penetrate if the part were submerged in it。开孔率:指网络的孔隙中一个材料,是开放的,液体表面和诸如水可以穿透如果部分被淹没在它。Closed porosity: refers to those pores that have become sealed within the grain structure 。封闭的孔隙度:指那些毛孔,已经成为密封在粒结构Pores affect the strength of ceramics in two ways：（影响强度的毛孔陶瓷两种方式）、they produce stress concentrations. Once the stress reaches a critical level, a crack will form and propagate.他们产生应力集中。一旦压力达到临界水平,裂纹形成和传播。、pores reduce the cross-sectional areas over which a load can be applied and, consequently, lower the stress that these materials can support。毛孔减少截面的负载可以应用,因此,降低压力,这些材料能支持。Conventional ceramic processing（传统陶瓷处理）；manufacture of the powder ,its calcinations ,milling ,grading and mixing ,incorporating additives ,shape forming , drying and densification. 制造的粉末,其煅烧、铣、分级和混合,包含添加剂、形状形成、干燥和致密化。三、GLASS（玻璃）1、the measured mechanical strength of glass is much lower than the theoretical strength测量的机械强度的玻璃远低于理论强度causes of this loss of strength ：、the presence of surface defects, such as caused by chemical corrosion or mechanical abrasion。表面缺陷的出现,例如由化学腐蚀或机械磨损。、If the glass is cooled too rapidly it does not have time to release stresses set up within it during cooling . these are frozen-in and can cause the glass to shatter when it becomes a solid.如果玻璃冷却过快它没有时间释放强调建立在它在冷却。这些都是“冻结”,可以使玻璃破碎时,它变成了一个坚实的。the transparency is explained by two properties :透明度是解释为两个属性:first ,it has no surface of internal structure which gives reflection or scattering。second ,it has no free electrons which can interact with the electron magnetic nature of wave motion including visible light 首先,它没有表面的内部结构,给反射或散射。第二,它没有自由电子,可以与电子磁性质的波动包括可见光四、CEMENT CONCRETE（水泥混凝土）ConcreteThe properties of the flesh or plastic concrete:肉体的属性或塑性混凝土:1. the wetness or dryness of the mix is referred to as the consistency or slump(湿润或干燥的组合称为一致性或衰退)2. uniformity indicates that the concrete is mixed thoroughly ,has a standard appearance ,and all ingredients are evenly distributed in the mix .一致性表明,混凝土和彻底,有一个标准的外观,和所有的原料都是均匀分布的组合。3. Workability is the ease with which concrete is placed and consolidated.The properties of hardened concrete (硬化混凝土的性质)一致性表明,混凝土和彻底,有一个标准的外观,和所有的原料都是均匀分布的组合。1. Hardened concrete should be durable, strong, watertight, and resistant to abrasion.硬化混凝土应该耐用,强壮,水密和耐磨损。2. Concrete must be durable enough to withstand extreme exposure conditions and to give long service with a minimum of upkeep.混凝土必须是持久的,足以承受极端的曝光条件和给长期服务,最低的保养。3. The most destructive weathering factor that can act on concrete is the freezing and thawing if concrete while it is wet or moist.最具破坏性的风化因素,可以作用于混凝土冻融如果混凝土虽然湿或潮湿。4. Concrete must be strong enough to carry the heavy loads placed on it.混凝土必须足以携带重物放在它。(混凝土的硬化是水和水泥之间发生化学和物理作用的结果。按阶段来分:产生快速放热期(第一阶段)大约15 min停止,随后为潜伏期(第二阶段)， 13 h出现初凝,此时潜伏期结束,进入第三阶段,再出现激烈反应,硅酸盐继续水化且速度加快,直到末期达到最大反应速度,亦即达到最大放热率,58 h产生终凝并开始早期硬化,以后反应速度再慢下来(第四阶段),在1214 h内达到稳定期。初凝相当于第二阶段结束,终凝相当于第三阶段结束而达到最大的化学反应速度,相应达到最大放热率。)5、Properties of concrete (混凝土的性能)a) concrete hardens in the presence of water .混凝土硬化在水的存在。b) it does not corrode or decay它不受腐蚀或腐烂c) freshly mixed concrete can be formed into any shape新拌混凝土可以形成任何形状d) concrete can be molded at normal temperatures混凝土塑造在正常温度e) can withstand heat and fire 能够承受加热和火Variables that influence concrete quality：aggregate gradation；water-cement ratio；air entrainment骨料级配;水灰比; 夹杂空气strength test used as hardened concrete :first strength of concrete, in compression, tension, shear, or a combination of these ,has, in most cases ,a direct influence on the load-carrying capacity of both plain and reinforced structures ;second the properties of hardened concrete ,those concerning strength can usually be determined most easily third by means of correlations wit h other more complicated tests ,the results of strength tests can be used as qualitative indications of other properties of hardened concrete 首先对混凝土强度、压缩、紧张、剪切、或组合这些,已经,在大多数情况下,直接影响的承载力两平原和钢筋结构; 第二个属性的硬化混凝土,那些关于强度通常可以确定最容易第三个通过其他更复杂的相关性机智h测试,测试结果的力量可以用作定性的迹象其他属性的硬化混凝土硅酸盐水泥的生产:两磨（磨原料，磨石膏）一烧（clinker熟料）；basic components of concrete :cement ,aggregate ,water ,additives五、POLYMER（聚合物）A Polymers is macromolecule (大分子）built up by the linking together of large numbers of much smaller molecules性能：low strength, low melting point flexible easily to be formed into different shapes Addition polymerization（加聚反应）Here are three significant reactions that take place in addition polymerization: initiation, propagation, and termination.入门、迁移、记录保管和终止。initiation (birth) 链引发propagation (growth) 链增长termination (death) 链终止Termination Reaction: Termination typically occurs in two ways:combination(偶合终止) and disproportionate(歧化终止)Combination occurs when the polymers growth is stopped by free electrons from two growing chains that join and form a single chain.结合发生在聚合物的增长是停在自由电子从两个增长链,加入和形成一个链。反应式Disproportionation halts the propagation reaction when a free radical strips a hydrogen atom from an active chain. A carbon-carbon double bond takes the place of the missing hydrogen.歧化中断传播反应当自由基带一个氢原子从一个活跃的链。一个碳碳双键取代失踪的氢。反应式Living polymerization: There exists a type of addition polymerization that does not undergo a termination reaction. This so-called “living polymerization” continues until the monomer supply has been exhausted Polymers vary in their mechanical behavior depending on the degree of crystallinity , degree of crosslinking, and the values of Tg and Tm.生活聚合:存在一个类型的加成聚合反应,不经历一个终止反应。这个所谓的“生活聚合”将继续,直到单体供应已经筋疲力尽聚合物都有不同的力学行为取决于结晶度、交联度、Tg和Tm的值。There are two types of plastics：flexible plastics（柔性塑料） and rigid plastics（刚性塑料）.The flexible plastics possess moderate to high degrees of crystallinity and a wide range of Tm and Tg values. They have moderate to high tensile strengths, and ultimate elongation.灵活的塑料具有中等到高程度的结晶度和广泛的Tm和Tg值。他们有中等到高强度的优势,和极限伸长。The rigid plastics have high moduli and moderate to high tensile strengths, they undergo very small elongations before rupturing.有很高的硬质塑料模和中等到高强度的优势,他们经历非常小的elongations断开之前。Tm-polt of melt temperature Tg-glass transition temperature Tg/Tm=0.5-0.8A highly flexible chain has a low Tg and strong intermolecular forces tend to raise Tg and also increase crystallinity, the controlling factor in determining Tg is chain flexibility一个高度灵活的链有一个低Tg和强大的分子间力倾向于提高Tg和结晶度也增加,控制因素在决定Tg是链的灵活性六、COMPOSITE（复合材料）Definition of Composite（复合材料的定义） A composite is a combined material created by the synthetic assembly of two or more components a selected filler or reinforcing agent and a compatible matrix (基体) binder (e.g. a res